This invention relates generally to thermal transfer recording apparatus and, more particularly, to a platen roller apparatus for a thermal transfer recording apparatus using a sheet of recording paper.
Japanese Utility Model No. 63-198551 discloses a platen roller of a conventional thermal transfer recording apparatus.
A recording sheet positioning mechanism of the conventional recording apparatus will be described below with reference to FIGS. 15 and 16 of the accompanying drawings.
A cylindrical platen roller 1A has a cut-out outer peripheral portion 1B disposed in parallel to a longitudinal center axis of a rotary platen shaft 2A. An integrally formed recording sheet fixing member 5A is provided on the platen roller 1A so as to be rotatable on rotational supporting points 1C on axial-end surfaces of the platen roller 1A. The recording sheet fixing member 5A serves to retain one end of a recording sheet 3A wound around the platen roller 1A by pressing the end of the sheet against the cut-out portion 1B in a direction toward the platen shaft 2A. Springs 6A are stretched between the recording sheet fixing member 5A and the platen roller 1A to provide a rotational force for retaining the recording sheet 3A. The recording sheet fixing member 5A has a positioning portion 5B for positioning the recording sheet 3A which is supplied to the gap between the cut-out portion 1B of the platen roller 1A and the recording sheet fixing member 5A.
FIG. 17 also shows another conventional roller of a similar type.